Predictable Identities: 15 – Newcomblike, Part I

“Do you like money?”

You spin around to see a strange child. You could’ve sworn you were alone on this street just a second ago. “Everyone likes money, kid,” you reply, “but I’m not getting sucked into another MLM scheme.” 

“This isn’t MLM, it’s LDT!” The child presses an envelope into your hand. “Open it.”

You do, it contains several $100 bills. “What’s the trick?” you ask. “And what’s your name?”

“The name’s Newcomb, and the trick was hacking into your phone last month.” The child smiles. “I’ve studied your behavior, and made some predictions. Specifically, I predicted whether you will take the envelope or leave the bills on the ground and go straight home after you hear me speak. If I predicted you would do the latter, I deposited $1,000,000 into your bank account 5 minutes ago. If I predicted you’ll take the cash, I retweeted Trump from your Twitter handle. By the way, I’ve been playing this game for a while and never got a prediction wrong. Goodbye!”

You look down at the cash. “Wait, what if…” but as you look up, the child is gone like an expired snap.

Do you take the cash or leave it and go home? Or do you hate philosophical thought experiments? Alright, let’s talk about something completely different.

Your employer decides on bonuses in December, but the bonuses are only paid out (and found out) in March. If the company predicted that you would slack off in Q1, your bonus is small, and if they thought you’d hustle it’s generous. You planned to quit at the end of March anyway, how hard do you work until then?

A leasing agent says she has another application for your dream apartment, but she’ll let you rent it because she feels you’ll work extra hard to maintain the furnishings. Do you?

Series Navigation<< Predictable Identities: 14 – Frameworks are Fake

Get Ribbonfarm in your inbox

Get new post updates by email

New post updates are sent out once a week

About Jacob Falkovich

Jacob is so proud of his blog,, that it's on his online dating profiles. He also tweets @yashkaf.


  1. Re: the child — clearly I should leave the money on the ground, because I might actually be part of a simulation designed to predict what the real me would do, and I want to ensure that the real me has a shot at the million dollars.

    • This is quite interesting. The argument you made, that if someone is predicting you they are probably simulating you and you can’t tell whether you’re *you* or the simulation, is exactly the intuition pump that convinced me and made Newcomb’s Problem “click” for me. After hearing that I intuitively see one-boxing as the obviously right thing to do. And yet for other people it’s a completely nonsensical argument, so obviously wrong that hearing it entrenches them further in two-boxing. I wonder what it means that some people find it so easy to accept that their most cherished possession, their own subjective experience, is not a special and unique thing but something that can be replicated by good enough simulators.

  2. 1) take the cash, this kid gotta be shitting me (also who cares about me tweeting Trump)

    2) mediocre work, as per usual.

    3) i actually do work extra hard to keep the furnishings, how’d she know?

  3. Deepthi Amarasuriya says

    I’m imagining the child to be the young Sheldon.

Leave a Comment


This site uses Akismet to reduce spam. Learn how your comment data is processed.